This specification relates generally to weather hazard warnings. More particularly, this specification relates to detection of weather hazards related to ice crystals.
Conventional aircraft hazard weather radar systems, such as the WXR 2100 MultiScan™ radar system manufactured by Rockwell Collins, Inc., have Doppler capabilities and are capable of detecting at least four parameters: weather range, weather reflectivity, weather velocity, and weather spectral width or velocity variation. The weather reflectivity is typically scaled to green, yellow, and red color levels that are related to rainfall rate. The radar-detected radial velocity variation can be scaled to a turbulence level and displayed as magenta. Such weather radar systems can conduct vertical sweeps and obtain reflectivity parameters at various altitudes.
Ice crystals pose threats to aircraft and their components. For example, sensors can provide improper readings when clogged by ice. Probes and engines can also be susceptible to damage caused by mixed phase and glaciated ice crystals when operating near areas of deep convection and at higher altitudes. Engine rollback issues are believed to be related to ice crystal accretion, followed by aggregate detachment in solid form before continuing through the aircraft engine. High efficiency engines are believed to be more susceptible to damage caused by ice crystals.
Radar reflectivity levels in and around the convective regions at high altitudes associated with high altitude, thin ice crystal formation have typically been very low and can be difficult to detect. Conventional X-band radar systems provide insufficient energy on the target to detect and discriminate high altitude ice crystal clouds. It is difficult to distinguish low reflectivity precipitation areas from areas of high altitude ice crystal (HAIC) formation and HAIC clouds (HAIC2). Detection and display of high altitude ice crystallization areas is desirous because the icing events caused by HAIC and/or high altitude ice crystal cloud (HAIC2) conditions can have a direct impact on aircraft, crew and passengers depending on the severity of the accretion.
Thus, there is a need for an aircraft hazard warning system and method that senses an inferred or non-inferred high altitude ice crystal (HAIC) or high altitude ice crystal cloud (HAIC2) conditions. There is also a need for a hazard detection system that detects and displays high altitude associated threat (HAIC) or high altitude ice crystal cloud (HAIC2) conditions. There is also a need for an inferred and/or non-inferred HAIC or HAIC2 detection system and method. Still further, there is a need for a signal processing technique for increasing signal-to-noise ratios (SNRs) associated with radar returns for HAIC or HAIC2 detection. Yet further, there is a need for an aircraft hazard warning system that alerts a pilot to HAIC or HAIC2 conditions.
It would be desirable to provide a system and/or method that provides one or more of these or other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the aforementioned needs.